Foliar application of chitosan-zinc oxide nanoparticles improved the yield of peaby modulating photosynthetic pigments, water status, and osmotic concentrationunder water stress

Among the various stresses affecting crop productivity, drought is a major challenge, particularly for leguminous crops like peas.The present study investigated the potential of chitosan-zinc oxide nanoparticles (CHT-ZnO NPs) to enhance drought tolerance in Pisum sativum L. through foliar application.The nanoparticles were synthesized via ion gelation, characterized before application using field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), and X-ray photoelectron spectroscopy (XPS).Thereafter, CHT-ZnO NPs were applied to pea plants at concentrations of 200 ppm and 400 ppm as well as ZnSO 4 under different drought stress levels as per treatment plan.The results demonstrated that CHT-ZnO NPs significantly enhanced physiological and yield attributes of tested plant, even under moderate to severe drought stress.Notably, the 200 ppm dose of CHT-ZnO NPs showed the most significant improvement in chlorophyll contents (42.8 to 31.9%) and overall yield (54.6 to 43.2%), compared to their respective control under moderate to severe drought (60 and 40% field capacity (FC), respectively), thereby mitigating the adverse effects of drought.These findings suggest that the foliar application of CHT-ZnO NPs could become a promising strategy to improve drought resilience in pea crops.K e y w o r d s: chitosan, drought stress,